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On the basis of glacial landforms interpreted by means of Landsat satellite imagery and ice‐flow data obtained by other methods, the Scandinavian ice sheet has been observed to have divided at the deglaciation stage into several ice lobes. The ice lobes were more active parts of the uniform ice sheet. They represent parts that had bordered on each other in different directions or on more passive portions of the ice. The reasons for the appearance of separate ice lobes were evidently the Fennoscandian topography, the location of accumulation areas, and regional differences in the amounts of ice generated. In the boundary zones of the different ice lobes, there occur exceptionally large glaciofluvial forms and moraines (interlobate complexes). An area of passive ice was often between ice lobes, and in such areas there occur no noteworthy eskers, marginal formations or streamlined forms. In the part of Finland located on the southern side of the Arctic Circle, six different ice lobes and four major areas of passive ice are interpreted to have existed.

Mapping of striae trends, macro-scale erosion forms, drumlins, morainic ridges, eskers, till fabric and boulder fans has facilitated reconstruction of glacial dynamics in terms of ice streams, marginal ice lobes and interlobate zones. Data were recorded in a computerised geographical information system (GIS).Data on oriented glaciogenic elements are compared with the evolving patterns of glacial flow. The oldest flow occurred at a distance of several hundred kilometres inside the ice margin, while the later flows were dependent on the dynamics of the ice streams and fan-shaped ice lobes. A model is developed for the zonation of subglacial processes such as erosion, deposition and till deformation beneath the ice sheet. Most of the glacial forms, as well as lower till, were generated in a zone of basal melting and fast ice flow which existed some hundred kilometres from the receding margin and was associated with the formation of ice streams. These results are consistent with recent reconstructions of basal hydrology using mathematical models.Ice streams were important for deglaciation dynamics. In the course of deglaciation, decreased shear stress on the water-saturated substratum resulted in ice-bed uncoupling which lowered the profile and accelerated flow in the ice streams. This did not happen in interstream areas as reflected by the glacial geomorphology typical of inactive ice.

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